Fossil sites in the Arctic from about 50 million years ago provide a glimpse of life that evolved in the tropical forest under extreme greenhouse conditions. The Arctic was a warm, wet, swampy, forested place 50 million years ago. Ellesmere Island is a key fossil site in Canada's High Arctic, where the remains of unique mammal species can tell us what the environment and animals of the Eocene Epoch were like. Scientists are studying these fossils to better understand our warming planet. Hear paleontologists Natalia Rybczynski and Mary Dawson – the first to identify fossil mammals from the Arctic – describe their research and how it helps recreate life during the greenhouse period 50 million years ago.